Strawberry plant named &#39;Portola&#39;

ABSTRACT

This invention relates to a new and distinctive day-neutral type strawberry designated as ‘Portola’. ‘Portola’ is a day-neutral (everbearing) cultivar similar to ‘Diamante’ (U.S. Plant Pat. No.  13,079 ) but with higher yield and better quality fruit, better disease resistance and better flavor; it is similar to ‘Albion’ (U.S. Plant Pat. No.  16,228 ) for fruit quality but with higher yield, and larger and lighter colored fruit.

GENUS AND SPECIES

The strawberry cultivar of this invention is botanically identified as Fragaria×ananassa Duch.

VARIETY DENOMINATION

The variety denomination is ‘Portola’.

BACKGROUND OF THE INVENTION

This invention relates to a new and distinctive day-neutral type cultivar designated as ‘Portola’, which resulted from a cross performed in 2001 between advance selections Cal 97.93-7 and Cal 97.209-1. ‘Portola’ was first fruited at the University of California Wolfskill Experimental Orchard, near Winters, Calif. in 2002, where it was selected, originally designated Cal 1.206-5, and propagated asexually by runners. Following selection and during testing the plant of this selection was designated ‘CN224’ and, later for introduction into commerce, ‘Portola’. Asexual propagules from this original source have been tested at the Watsonville Strawberry Research Facility, the South Coast Research and Extension Center, and to a limited extent in grower fields starting in 2005.

BRIEF SUMMARY OF THE INVENTION

‘Portola’ is a day-neutral (everbearing) cultivar similar to ‘Diamante’ (U.S. Plant Pat. No. 13,079) but with higher yield and better quality fruit, better disease resistance and better flavor; it is similar to ‘Albion’ (U.S. Plant Pat. No. 16,228) for fruit quality but with higher yield, and larger and lighter colored fruit.

BRIEF DESCRIPTION OF THE DRAWINGS

The figures depict various characteristics of the ‘Portola’ cultivar.

FIG. 1 shows the general flowering and fruiting characteristics of the plant in a field planting.

FIG. 2 shows a typical leaf at mid-season.

FIG. 3 shows a representative mid-season fruit.

DETAILED DESCRIPTION OF THE INVENTION

‘Portola’ is typical of day-neutral strawberry cultivars and produces fruit regardless of day length when treated appropriately in arid, subtropical climates. ‘Portola’ is moderate to strong in expressing the day-neutral character, being stronger in flowering response to ‘Diamante’ (U.S. Plant Pat. No. 10,435) and Albion (U.S. Plant Pat. No. 16,228), and more similar in flowering to ‘Fern’ (U.S. Plant Pat. No. 5267) or ‘Irvine’ (U.S. Plant Pat. No. 7172). The production pattern for ‘Portola’ is similar to that for ‘Albion’, although it is earlier to initiate production. ‘Portola’ will be of special interest for winter plantings and in summer plantings where ‘Diamante’ and ‘Albion’ have been successful. It is expected to perform especially well in spring and summer planting systems aimed at fall fruit production.

-   Plants and foliage: Fruiting plants of ‘Portola’ are similar in     morphology to ‘Diamante’ and ‘Albion’ although somewhat larger     throughout the season; ‘Portola’ plants are similar in size to     plants of ‘Aromas’ but more dense. Comparative statistics for foliar     characters near mid-season are given for ‘Portola’ and the three     comparison cultivars in Table 1. Individual leaflets for ‘Portola’     are similar in shape and size to the comparison cultivars. Leaves     (including petioles) for ‘Portola’ are longer than those for     ‘Diamante’ and ‘Albion’, mostly due to greater petiole length.     Petioles are generally thinner than those of the comparison     cultivars and tend to have heavy pubescence. The adaxial (upper) and     abaxial (lower) surfaces of leaves for ‘Portola’ are similar in     color to the comparison cultivars at mid season, but slightly     lighter early in the season. Leaves of ‘Portola’ have similar     concavity to ‘Aromas’, ‘Diamante’, and ‘Albion’. -   Disease and pest reaction: ‘Portola’ is moderately resistant to     powdery mildew (Sphaerotheca macularis), Anthracnose crown rot     (Colletotrichum acutatum), and Verticillium wilt (Verticillium     dahliae); it is very resistant to Phytophthora crown rot     (Phytophthora cactorum) and common leaf spot (Ramularia tulasnei)     (Table 3). When treated properly, it has tolerance to two-spotted     spider mites (Tetranychus urticae) equal to that for the comparison     cultivars. ‘Portola’ is tolerant to strawberry viruses encountered     in California.

TABLE 1 Foliar and plant characteristics for ‘Portolat’, ‘Aromas’, ‘Diamante’, and ‘Albion’. Cultivar Foliar Character ‘Aromas’ ‘Diamante’ ‘Albion’ ‘Portola’ Plant height (mm) mean 272 220 223 267 range 240-300 190-240 170-290 240-300 Plant spread (mm) mean 323 316 295 313 range 300-360 265-385 270-315 295-335 Mid-tier leaflet Length (mm) mean 79 78 70 71 range 70-90 60-90 60-80 65-80 Width (mm) mean 74 77 68 69 range 70-80 55-90 60-80 60-90 Mid-tier leaf Length (mm) mean 113 99 99 107 range 100-120  80-120 90-110 100-120 Width (mm) mean 135 134 122 136 range 120-150  90-150 105-135 120-150 Leaf components Petiole length (mm) mean 174 114 122 159 range 140-210 100-130  95-180 110-215 Petiole diameter (mm) mean 4.5 5.2 4.9 3.9 range 4-6 4-7 4-6 3-5 Petiolule length (mm) mean 6.6 5.2 6.7 7.0 range 4.3-7.5 4.0-7.6 5.0-8.0 5-8 #leaflets/leaf 3 3 3 3 Leaf convexity some flat, some flat, some flat, some flat, most slight most slight most slight most slight concave concave concave concave Serrations number/leaf 19.9 20.2 23.3 24.4 range 16-24 16-24 21-27 21-28 shape rounded to rounded to semi-pointed most semi-pointed semi-pointed rounded, some semi- pointed Leaf pubescence moderate moderate- moderate heavy heavy Petiole pubescence Moderate- heavy heavy heavy density heavy direction perpendicular perpendicular perpendicular perpendicular Petiole color (Munsell) 5 GY 8/8 7.5 GY 9/4 5 GY 8/8 5 GY 8/8 Stipule length (mm) mean 34.2 31.6 32.5 33.4 range 30-39 22-36 24-37 29-40 Stipule color core 7.5 GY 8/7 7.5 GY8/7 5 GY 8/7 2.5 GY8/9 margins 2.5 GY 9/3 5 GY 6/8 5 GY 6/8 5 GY 7/10 Stolon base diameter 3.0 3.2 3.0 3.2 (mm) Stolons per nursery 33.0 29.0 26.9 32.0 mother plant Venation pattern pinnate pinnate pinnate pinnate color 2.5 GY 5/5 10 GY 5/5 2.5 GY 6/8 10 Y 6/7

-   Flowering, fruiting, fruit, and production characteristics:     ‘Portola’ is similar to other California day-neutral cultivars     (e.g., ‘Diamante’ and ‘Albion’) in that it will flower independently     of day length, given appropriate temperature and horticultural     conditions. Comparative statistics for flower and fruit characters     near mid-season are given for ‘Portola’ and three other cultivars in     Table 4. The primary flowers for ‘Portola’ are slightly larger than     those of the ‘Aromas’ and ‘Diamante’ but smaller than those of     ‘Albion’. The calyx for ‘Portola’ is distinctly larger than the     corolla on primary fruit; the sepals are similar in length and shape     to those of the comparison cultivars. The calyx for ‘Portola’ varies     in position but is usually less reflexed than for ‘Aromas’ or     ‘Diamante’, much less than that of ‘Albion’. The fruit shape for     ‘Portola’ can vary but is typically a medium to short and highly     symmetrical conic. It is easily distinguished by fruit shape from     ‘Aromas’ (shortened and rounded conic), ‘Diamante’ (usually a flat     conic) or ‘Albion’ (long conic); ‘Portola’ usually has a greater     proportion of symmetrical fruit than the comparison cultivars,     especially early in the fruiting season. External fruit color for     ‘Portola’ is slightly lighter than ‘Aromas’ or ‘Albion’, distinctly     darker than for ‘Diamante’; internal color is somewhat darker with     greater red pigment than for the comparison cultivars (Table 2).     Achenes vary from yellow to dark red, but are usually red, and range     from even with the fruit surface to slightly indented. ‘Portola’ has     been tested under a variety of cultural regimes, and optimal     performance is obtained when nursery treatments and nutritional     programs similar to those for ‘Albion’, ‘Diamante’, and ‘Aromas’ are     used. In general, ‘Portola’ is more vigorous than the comparison     cultivars and is less sensitive to low chilling. ‘Portola’ is     distinctly stronger in day-neutrality than the comparison cultivars     and produces greater quantities of fruit when established with     spring or summer plantings of long-term cold stored plant material.     ‘Portola’ retains excellent fruit quality in summer planting     systems. When treated with appropriate planting regimes, ‘Portola’     has larger fruit and produces greater individual-plant yield than     any of the comparison cultivars (Table 5). ‘Portola’ has a similar     production pattern to ‘Albion’ with most cultural treatments,     although it is substantially more adapted to early-season winter     planting. Commercial appearance ratings have been similar to or     higher than those for all of the comparison cultivars, especially     ‘Aromas’; these superior appearance scores translate directly into a     larger fraction of marketable fruit than is produced by the     comparison cultivars. Fruit for ‘Portola’ is substantially firmer     than fruit from ‘Aromas’, similar in firmness to the other     comparison cultivars. Subjectively, ‘Portola’ has outstanding     flavor. The fruit will be exceptional for both fresh market and     processing, and will be useful for home garden purposes.

TABLE 2 Foliar and fruit color characteristics for ‘Portola’ and three comparison cultivars. Color Cultivar Character ‘Aromas’ ‘Diamante’ ‘Albion’ ‘Portola’ Leaf color (CIELAB) Adaxial L* mean 35.1 34.8 34.7 34.3 range 32.7-37.7 32.6-36.8 32.8-36.7 31.6-35.5 a* mean −10.6 −10.4 −9.8 −9.8 range −8.2-−14.0 −8.7-−11.9 −9.4-−11.3 −8.0-−1.55 b* mean 13.8 13.8 12.8 13.1 range 11.2-18.1 12.2-16.6 10.7-15.6 11.0-15.7 Munsell 7.5 GY 4/4 5 GY 4/3 5 GY 4/3 5 GY 4/3 Abaxial L* mean 52.4 51.1 50.6 52.4 range 50.6-54.1 49.7-52.2 43.7-53.1 51.5-54.1 a* mean −11.6 −12.8 −12.4 −11.6 range −10.7-−13.6 −11.6-−14.9 −8.6-−11.4 −10.3-−13.6 b* mean 17.3 19.5 17.2 17.3 range 14.3-23.2 15.3-23.5 14.5-19.6 15.9-23.2 Munsell 10 GY 7/8 7.5 GY 6/8 7.5 GY 8/7 10 GY 7/8 Fruit color (CIELAB) External L* mean 34.2 40.8 36.5 34.3 range 31.2-38.3 35.5-45.4 32.8-40.1 31.4-37.2 a* mean 33.9 36.7 33.3 35.7 range 31.5-38.6 35.6-40.2 28.3-36.2 31.0-39.9 b* mean 14.1 21.2 17.6 15.9 range  9.1-16.5 18.8-25.7 12.2-24.9 13.4-20.6 Munsell 2.5 R 4/10 5 R 5/13 5 R 3/7 5 R 4/12 Internal L* mean 61.6 65.6 57.9 50.9 range 59.5-67.7 58.8-67.2 43.3-62.9 45.2-56.7 a* mean 14.7 5.6 19.0 30.4 range  7.6-19.2 3.0-9.5  7.9-27.7 24.2-36.6 b* mean 20.2 15.8 21.0 28.0 range 16.1-22.5 14.5-18.2 13.2-27.2 23.7-31.4 Munsell 5 R 6/11 10 R 7/9 7.5 R 4/11 7.5 R 5/13 Achene color 7.5 R 4/11 7.5 R 4/11 10 R 5/6 10 R 4/9 Munsell *CIELAB is the abbreviation of the international color system known as “Commission Internationale De L' Eclairage” 1978. For recommendations concerning uniform color spaces, color difference equations, and psychometric color terms see Supplement No. 2 of CIE Publication No. 15, Paris.

TABLE 3 Disease resistance scores for ‘Portola’ and three comparison cultivars; Phytophthora and Verticillium scores were obtained in evaluations conducted in 2004-2006, Colletotrichum was evaluated in 2005-2006. Phytophthora Verticillium Colletotrichum Resistance Score Resistance Score Resistance Score Genotype (5 = best) (5 = best) (5 = best ‘Aromas’ 4.0 4.5 2.4 ‘Diamante’ 2.0 2.8 2.6 ‘Albion’ 4.3 3.8 3.1 ‘Portola’ 4.4 3.3 2.6

TABLE 4 Flower and fruit characters for ‘Portola’ and three comparison cultivars. Cultivar Character ‘Aromas’ ‘Diamante’ ‘Albion’ ‘Portola’ Petal number mean 5.5 5.4 5.6 6.8 range 5-7 5-6 5-7 5-8 Petal shape apex truncate to truncate to truncate to truncate to slightly slightly obtuse slightly slightly base obtuse attenuate obtuse obtuse margin attenuate entire attenuate attenuate entire entire entire Petal length (mm) mean 10.1 9.2 9.6 11.1 range  8-11  7-13  8-11  8-13 Petal width (mm) mean 11.8 10.6 9.0 12.4 range 10-13 10-13  7-10  9-14 Flower position most even most even most most (relative to foliage) some some internal exposed, exposed, exposed and exposed some even some even Calyx diam. (mm) mean 31.3 32.0 37.5 36.0 range 28-33 25-41 31-48 31-42 Corolla diam. (mm) mean 31.2 23.9 27.8 32.2 range 26-35 18-31 23-33 24-39 Sepal length (mm) mean 12.3 12.1 14.1 12.5 range  8-15 10-15 11-18  9-15 Sepal width (mm) mean 6.4 6.7 6.6 7.3 range 3-9 5-9  4-10 5-9 Sepal color (Munsell) 7.5 GY 6/8 5 GY 5/6 2.5 GY 6/8 5 GY 5/6 Pedicel length (mm) mean 172 140 218 225 range 112-230 110-165 180-270 200-240 Pedicel diameter (mm) mean 4.4 5.3 3.1 4.3 range 4-6 4-6 2-4 3-6 Pedicel color 5 GY 6/8 5 GY 7/10 5 GY 6/8 5 GY 6/8 Fruit shape Fruit length (mm) mean 46.6 46.4 61.7 50.4 range 42-52 39-50 50-76 43-57 Fruit width (mm) mean 39.4 40.7 46.6 47.7 range 37-43 38-46 37-52 43-54 Length/width ratio 1.2 1.1 1.3 1.1 range 1.0-1.4 1.0-1.2 1.2-1.5 1.0-1.2 subjective mostly rounded to flat most long Medium- medium to conic symmetrical short short flat conic symmetrical conic conic Primary/secondary fruit comparison size (subjective)  60-80%  60-80%  60-70%  75-85% shape similar shape similar shape similar shape similar shape Extent/size of hollow core small-absent small-absent small- small- medium medium Calyx position indented- even-indented even-reflexed even- even with indented neck size relative to fruit equal or equal or equal or equal or greater than greater than greater than greater than fruit fruit diameter fruit diameter fruit diameter diameter Seed position indented- indented-even indented- indented- extruded extruded even Adherence of Calyx to intermediate intermediate intermediate intermediate Fruit

Flower measurements and fruit measurements obtained May 9-Jun. 6, 2006, subjective observations obtained Jul. 31, 2006.

TABLE 5 Performance ‘Portola’ and three comparison cultivars evaluated at the Watsonville Research Facility in 2005-7. All plants for these trials were harvested from a commercial nursery near Macdoel, CA on October 15-16, and transplanted after 18-21 days supplemental storage. Fruit harvest was initiated in early April and continued through the first week of October. (52″ 2-row beds, 17,300 plants/acre). Appearance Fruit Yield Score Size Item (g/plant) (5 = best) (g/fruit) Firmness ‘Aromas’ 3,108 3.1 27.0 9.6 ‘Diamante’ 2,653 3.5 31.2 11.0 ‘Albion’ 2,461 3.9 30.5 11.1 ‘Portola’ 3,336 3.6 32.0 10.2 

1. A new and distinct cultivar of strawberry plant having the characteristics substantially as described and illustrated herein. 